Selenium (Selenomethionine)

Source

L-Selenomethionine

Chemical Name

Atomic number 34

Immune support

Selenium improves immunologic function by increasing the activity of interleukin-2 (IL-2) and promoting the normal growth and development of T helper cells.

As an essential cofactor of the antioxidant enzyme glutathione peroxidase, selenium helps avert free radical damage and works with vitamin E. It supports normal growth, fertility, detoxification and the immune system.

Other uses

The mechanisms of action selenium undertakes in the human body may be important in treating acquired immunodeficiency syndrome (AIDS) because selenium deficiency is common in this condition. There is preliminary experimental evidence that selenium inhibits reverse transcriptase and replication of human immunodeficiency virus (HIV). However, there is also some evidence that selenium may improve subjective feelings of well-being in patients infected with HIV, but it does not appear to affect overall outcomes. Selenium deficiency is associated with increased viral shedding in women infected with HIV. Supplementing the diet of these women with selenium may decrease the transmission of AIDS. There is also evidence that suggests that deficiency of selenium may increase inflammatory lung damage caused during influenza virus infection. Selenium also might protect patients infected with hepatitis B or C from developing liver cancer.

A disease that causes underactive thyroid (autoimmune thyroiditis). Research shows that taking up to 200 mcg of selenium daily along with thyroid hormone might decrease antibodies in the body that contribute to this condition. Selenium might also help improve mood, general feelings of well-being, and quality of life in people with this condition. Taking selenium doses under 200 mcg daily might not be as effective, and it might be more beneficial in people with more severe cases.

A disorder that affects the bones and joints, usually in people with selenium deficiency (Kashin-Beck disease). Some research shows that adding salt enriched with selenium to food can prevent Kashin-Beck disease in children. But selenium does not seem to improve joint pain or movement in children with Kashin-Beck disease.

A pregnancy complication marked by high blood pressure and protein in the urine (pre-eclampsia). Pregnant women with low levels of selenium in the blood might have a higher chance of developing pre-eclampsia. Pre-eclampsia is a serious complication of pregnancy. Pregnant women taking selenium 60-100 mcg daily for up to 6 months during pregnancy might have a lower chance of having pre-eclampsia.

How it works

Selenium is important for making many body processes work correctly. It seems to increase the action of antioxidants.

Safety

When taken by mouth: Selenium is LIKELY SAFE for most people when taken by mouth in doses less than 400 mcg daily, short-term. However, selenium is POSSIBLY UNSAFE when taken by mouth in high doses or for a long time. Taking doses above 400 mcg can increase the risk of developing selenium toxicity. Taking lower doses for a long time, such as doses that are higher than the recommended dietary allowance (RDA), can also increase the risk of developing diabetes.

Selenium can cause muscle tenderness, tremor, lightheadedness, facial flushing, blood clotting problems, liver and kidney problems, and other side effects. High doses of selenium can cause significant side effects including nausea, vomiting, nail changes, loss of energy, and irritability. Poisoning from long-term use is similar to arsenic poisoning, with symptoms including hair loss, white horizontal streaking on fingernails, nail inflammation, fatigue, irritability, nausea, vomiting, garlic breath odor, and a metallic taste.

Special Precautions & Warnings:

Pregnancy and breast-feeding: Selenium is POSSIBLY SAFE during pregnancy and breast-feeding when used short-term in amounts that are not above 400 mcg daily. Selenium is POSSIBLY UNSAFE in pregnancy and breastfeeding when taken by mouth in doses above 400 mcg daily. This dose might cause toxicity, and in HIV-positive women, it might increase virus levels in breast milk.

Children: Selenium is POSSIBLY SAFE when taken by mouth appropriately. Selenium seems to be safe when used short-term in doses below 45 mcg daily for infants up to age 6 months, 60 mcg daily for infants 7 to 12 months, 90 mcg daily for children 1 to 3 years, 150 mcg daily for children 4 to 8 years, 280 mcg daily for children 9 to 13 years, and 400 mcg daily for children age 14 years and older.

Autoimmune diseases: Selenium might stimulate the immune system. In theory, selenium might make autoimmune disease worse by stimulating the activity of the disease. People with autoimmune diseases such as multiple sclerosis, systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and other should avoid taking selenium supplements.

Hemodialysis: Blood levels of selenium can be low in people undergoing hemodialysis. Using a dialysis solution with selenium might increase selenium levels, but selenium supplementation might be needed for some people.

Under-active thyroid (hypothyroidism): Taking selenium can worsen hypothyroidism especially in people with iodine deficiency. In this case, you should take iodine along with selenium. Check with your healthcare provider.

Fertility problems in men: Selenium might decrease the ability of sperm to move, which could reduce fertility. If you are trying to father a child, don't take selenium supplements.

Skin cancer: Long-term use of selenium supplements might slightly increase the risk of skin cancer recurrence, but this is controversial. Until more is known about the possible increase in skin cancer risk, avoid long-term use of selenium supplements if you have ever had skin cancer.

Surgery: Selenium might increase the risk of bleeding during and after surgery. Stop taking selenium at least 2 weeks before a scheduled surgery.

Interactions with medications

Birth control pills (Contraceptive drugs)

Interaction Rating = Minor Be watchful with this combination.

Talk to your health provider.

Some research shows that women who take birth control pills might have increased blood levels of selenium. However, other research shows no change in selenium levels in women who take birth control pills. There isn't enough information to know if there is an important interaction between birth control pills and selenium.

Some birth control pills include ethinyl estradiol and levonorgestrel (Triphasil), ethinyl estradiol and norethindrone (Ortho-Novum 1/35, Ortho-Novum 7/7/7), and others.

Gold salts

Interaction Rating = Minor Be watchful with this combination.

Talk to your health provider.

Gold salts bind to selenium and decrease selenium in parts of the body. This might decrease the normal activity of selenium, possibly resulting in symptoms of selenium deficiency.

Gold salts include aurothioglucose (Solganal), gold sodium thiomalate (Aurolate), and auranofin (Ridaura).

Medications that decrease the immune system (Immunosuppressants)